This invention relates to an electrical contact material.
Ag-Sn-In system alloys which have been internally oxidized, are advantageously employed today as electrical contact materials. Since in their Ag matrices there are dispersed very minute particles of oxides of solute metal elements, electrical characteristics, particularly refractoriness afforded to the materials are excellent. However, it is observed sometimes that they show a comparatively high electrical resistance particularly at an initial stage of use. This comparatively high contact resistance brings about often a temperature raise of contact surfaces of the materials.
These phonomena, that is, high electrical contact resistances and surface temperature raise are chiefly due to segregation or depletion layers often seen at outer surface areas of Ag-Sn-In system alloys which have been internally oxidized.